Location: Cotton Structure and Quality Research
Title: Preliminary evidence of oxidation in standard oven drying of cotton: attenuated total reflectance/ Fourier transform spectroscopy, colorimetry, and particulate matter formation Authors
Submitted to: Textile Research Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 25, 2013
Publication Date: June 3, 2013
Citation: Fortier, C.A., Montalvo Jr, J.G., Von Hoven, T.M., Easson, M.W., Rodgers III, J.E., Condon, B.D. 2013. Preliminary evidence of oxidation in standard oven drying of cotton: attenuated total reflectance/ Fourier transform spectroscopy, colorimetry, and particulate matter formation. Textile Research Journal. 84(2)157-173 DOI: 10.1177/0040517513487785. Interpretive Summary: When cotton is oven-dried to determine the amount of moisture in the sample, there is evidence to suggest that particulate matter and oxidation products are formed. Analysis of these oxidation products and particulate matter may lead to a heightened understanding of the bias found in the standard oven drying method when compared to moisture analysis by the Karl Fisher Titration. Particulate matter was easily observed by the eye when when greased slides where placed above oven treated cotton samples. Attenuated Total Reflection Fourier Transform spectroscopy was also used to help identify oxidation products formed during the standard oven drying methods. When ATR/FT-IR absorbance and derivative math was applied to oxidized cotton samples, the data suggested that cellulose aldehyde may be formed when cotton samples are oven-dried at temperatures above 100 C. Colorimetry data also suggested oxidation took place by the browning of the cotton samples. When taken together, the experimental data revealed preliminary evidence to help explain the oxidation of cotton during oven drying that may directly affect the calculated moisture present in cotton samples.
Technical Abstract: Moisture is paramount to cotton fiber properties dictating harvesting, ginning, storage and spinning as well as others. Currently, oven drying in air is often utilized to generate the percentage of moisture in cotton fibers. Karl Fischer Titration another method for cotton moisture, has been compared to the oven drying method. The percentage of moisture as generated by the oven methods track those of Karl Fischer Titration, but there are differences between the two. In fact, a bias exists in the measured moisture loss employing the standard oven drying method. The aim of this study is to determine what is causing those differences. In addition, the moisture data collected via Karl Fischer Titration demonstrate smaller variances than those data collected in the oven. It is proposed that the bias in oven drying occurs by the formation of oxidation products or particulate matter being released by the cotton fibers during drying. This preliminary study investigates the particulate matter, the oxidation products by Attenuated Total Reflectance Fourier-Transform Infrared (ATR/FT-IR) spectroscopy, as well as the color differences of four different cottons dried in an air flow oven at different temperatures. It is postulated that thermal treatment of cotton samples in air can lead to the formation of multiple oxidation products observed by ATR/FTIR broad absorption bands.